The present invention relates to methods and systems for analyzing call specific data records for traffic through a telecommunication network in order to identify specific types of called parties, particularly ISPs.
The written description uses a large number of acronyms to refer to various services, messages and system components. Although generally known, use of several of these acronyms is not strictly standardized in the art. For purposes of this discussion, acronyms therefore will be defined as follows:
Address Complete Message (ACM)
Asynchronous Digital Subscriber Line (ADSL)
ANswer Message (ANM)
Application Service Part (ASP)
Automatic Message Accounting (AMA)
Automatic Number Identification (ANI)
BellCore AMA Format (BAF)
Carrier Access Billing System (CABS)
Call Detail Record (CDR)
Carrier Identification Code (CIC)
Centi-Call Second (CCS)
Central Office (CO)
Competitive Local Exchange Carrier (CLEC)
Common Channel Interoffice Signaling (CCIS)
Common Language Location Identifier (CLLI)
Comma Separated Values (CSV)
Customer Record Information System (CRIS)
Cyclic Redundancy Code (CRC)
Destination Point Code (DPC)
End Office (EO)
Executive Information System (EIS)
Fill In Signal Unit (FISU)
First-In, First-Out (FIFO)
Global Title Translation (GTT)
Graphical User Interface (GUI)
Initial Address Message (IAM)
Integrated Service Control Point (ISCP)
Integrated Services Digital Network (ISDN)
ISDN User Part (ISDN-UP or ISUP)
Inter-exchange Carrier (IXC)
Internet Service Provider (ISP)
Landing Zone (LZ)
Line Identification Data Base (LIDB)
Link Service Signaling Unit (LSSU)
Local Area Network (LAN)
Local Exchange Carrier (LEC)
Loop Maintenance Operations Systems (LMOS)
Message Processing Server (MPS)
Message Signaling Unit (MSU)
Message Transfer Part (MTP)
Multi-Dimensional DataBase (MDDB)
Numbering Plan Area (NPA)
Office Equipment (OE)
Online Analytical Processing (OLAP)
Origination Point Code (OPC)
Operations, Maintenance Application Part (OMAP)
Percentage Internet Usage (PIU)
Personal Computer (PC)
Public Switching Telephone Network (PSTN)
Release Complete Message (RLC)
Release Message (REL)
Revenue Accounting Office (RAO)
Service Control Point (SCP)
Service Switching Point (SSP)
Signaling Link Selection (SLC)
Signaling System 7 (SS7)
Signaling Point (SP)
Signaling Transfer Point (STP)
Structured Query Language (SQL)
Transaction Capabilities Applications Part (TCAP)
Wide Area Network (WAN)
Rapid changes and increases in demand for telecommunication services increase the pressures for cost effective engineering and upgrading of the telephone network. The demand for traditional telephone service continues to increase, but at a steady and readily predictable pace. Several newer types of traffic through the telephone network, however, are increasing at an exponential rate and impose new traffic patterns that exacerbate difficulties in meeting the new traffic demands. The most significant and burdensome of these new types of traffic relates to calls through the telephone network to Internet Service Providers (ISPs), to allow callers to access the Internet.
The most common form of Internet access relies on modems and analog telephone network connections. A modem of this type modulates data from a personal computer (PC) for transmission in the voice telephone band over a telephone connection to the Internet Service Provider (ISP) and demodulates data signals received from the ISP over such a link. The analog telephone modem operates at one subscriber premises end of a voice grade line to transmit and receive signals over the line and through the telephone switch network to and from another similar line and modem in communication with an ISP""s host equipment.
To access the Internet, the user activates her PC and modem to dial a number for the ISP. The telephone network switches the call through to a line going to a modem pool operated by the ISP. Once connected through the telephone network, the user logs on, and the ISP""s equipment provides communications over the worldwide packet switched network now commonly known as the Internet. This telephone-based operation provides the voice grade analog modem a unique power, the necessary connections for Internet access are virtually ubiquitous. Such modems allow users to call in from virtually any telephone line or wireless telephone (e.g. cellular) almost anywhere in the world.
However, the calling patterns for this type of data communications, particularly Internet access, are radically different from those of normal voice traffic. The sudden increase in popularity of access to the Internet and the difference in call-in traffic patterns have radically changed the loading placed on the telephone network.
Normal voice telephone calls tend to occur at random times, and the network typically routes the majority of such calls to random destinations. Also, the average hold times for such calls tend to be short, e.g. three minutes or less. By contrast, Internet traffic tends to have severe peak traffic times during any given twenty-four hour period, e.g. from 8:00 PM to 11:00 PM. Also, the network must route Internet access calls to a very small number of destinations, i.e. to the lines for modem pools operated by Internet Service Providers (ISPs). Instead of many parties calling each other randomly, many callers are all calling in to a limited number of service providers. Finally, hold times for Internet calls can last for hours. Some Internet users access the Internet when they sit down at their desks and leave the call connections up until they decide to turn their computers off, e.g. at the end of their day. If they leave their computers on all the time, the connections to the ISPs may stay up for days. These Internet traffic patterns add incredibly heavy traffic loads to the telephone network and tend to concentrate those loads in specific offices providing service to the ISPs.
The local exchange carriers (LECs) are considering a number of different options for relieving the congestion caused by Internet access traffic. Using existing technologies, these options include deploying more switches and trunk circuits and designing the connections of switches and trunks to the ISPs and their high-end users to minimize call switching and/or trunk congestion. For example, if there is a heavy concentration of ISP bound calls from a mid-town end office switch to an end office in the suburbs that serves the ISP, the LEC might install additional direct trunks between those offices to reduce the need for overflow routing through a tandem office. Within the mid-town office switch, the LEC might connect the high-end users that call the particular ISP to the same switch module that connects to the new direct trunks to the suburban end office, in order to reduce the inter-module switching load within the mid-town switch. Similarly, in the suburban office, the LEC would connect the new trunks to the same switch module that serves the ISP.
The carriers also are considering and experimenting with a number of options to off-load the Internet access traffic from the voice telephone network. Such options range from deployment of dedicated trunks to the modem pools of the ISPs to deployment of advanced digital loop carrier systems that can recognize data calls and switch such calls over to some link directly to a fast packet network. Other technologies, such as Asynchronous Digital Subscriber Line (ADSL) networks, provide a totally separate logical path for the data communications.
The various strategies intended to address the increasing traffic demands of Internet access, such as adding end offices, deploying specialized switching modules, installing ADSL networks, adding trunks, deploying more tandem offices and the like, all require considerable expense by the carriers. Accurate engineering, to minimize cost and yet reduce congestion and provide effective service to the various customers, becomes ever more essential. To provide effective engineering, it is necessary that the carrier understand the traffic involved. Such understanding requires accurate and complete traffic measurement. Accurate information also is necessary to resolve disputes, for example with the ISPs over service quality.
Understanding the loading caused by access calls to ISPs begins with identifying the ISPs. Large Internet Service Providers, such as America On-Line are known, both to the public and to the local exchange carriers. However, many smaller operators come and go in the ISP business. Typically, a company approaches a local carrier and subscribes to a number of business lines in a multi-line hunt group. A typical business connects telephone equipment to the lines, but unbeknownst to the carrier, an ISP connects a pool of modems to the lines. The company""s customers call the main number of the hunt group, and the telephone network routes the calls to the next available line in the group. The carrier often does not know the type of business that the company operates, in this case, that the company is another ISP.
A need therefore exists for an effective technique to measure and analyze unique traffic patterns, particularly as they relate to Internet access calls. A more specific need is for a technique to measure traffic, identify characteristic traffic patterns and determine therefrom the destinations serving as access points for otherwise unknown ISPs.
A number of techniques have been developed for monitoring operations of the public switching telephone network. While these prior techniques may be effective for some purposes, they have not proven effective for analyzing Internet access traffic or recognizing ISPs. To complete the understanding of the background of the invention, it may be helpful to briefly consider some of the prior techniques for network monitoring.
U.S. Pat. No. 5,475,732 Pester describes an SS7 Network Preventative Maintenance System for detecting potential SS7 and switched network troubles, automatically analyzing the troubles, and providing alarm and corrective action to avoid major network events. The Pester SS7 Real Time Monitor System described in that Patent is a multi-stage SS7 network preventative maintenance tool that traps SS7 messages, detects potential SS7 and switched network troubles, automatically analyzes those troubles, and provides alarm and corrective action instructions to maintenance personnel.
U.S. Pat. No. 5,592,530 to Brockman et al. relates to an SS7 monitoring system for evaluating the operations of telephone switches by capturing data between signaling nodes of a telephone switching system. The Brockman et al. surveillance equipment captures signaling information from different signaling network paths within a mated STP pair and correlates the fragmented messages for each monitored call. The system is capable of generating call detail records from the SS7 messages of a mated pair cluster, for use in billing and fraud detection.
While the above discussed Pester and Brockman et al. Patents describe the usefulness of monitoring an SS7 common channel interoffice signaling network for event detection, neither of these patents is directed to the particular problems of traffic measurement addressed by the present invention. The Pester Patent places emphasis on monitoring of the SS7 network itself in order to detect troubles in its functioning. The Brockman et al. Patent focuses on monitoring of all links to the STPs in a pair and the assembly of related SS7 signaling messages to form a record of call completions.
While these methodologies may be effective for their stated purposes there remains a distinct need for an efficient and effective tool for monitoring and analyzing types of traffic through the telephone network, to recognize unique patterns and identify key users involved in such traffic patterns. Attempts to use other more traditional approaches, such as the accumulation of data from the switches themselves and the Engineering and Administrative Data Acquisition System fell short of providing the desired information.
For example, today, a LEC conducts studies on usage in an office by setting up a xe2x80x9cbusy studyxe2x80x9d with respect to specific individual lines served through that office. It is not possible to look at all the traffic in the office at one time. Typically, the LEC can study maybe three different lines at a time. So in a 50,000-line office the LEC engineers can examine the traffic for up to three hundred lines at one time. Also, setting up and maintaining such studies are labor intensive. To conduct a meaningful number of studies throughout a large service area, a LEC virtually needs an army of clerical people whose main job function is setting up busy studies. Once set up, such a study may run for three weeks, but at the end of that time, it takes another two weeks to process the output and organize the results into a report. Results are not available in real-time. Even when results do become available, the study only shows data on a few lines that may or may not be causing blockage in the busy hour. If the lines were not properly selected, the busy study may be virtually meaningless to the network engineer trying to relieve congestion through the office. Also, traffic patterns are changing rapidly, e.g. as new ISPs obtain lines and go into service in already congested areas. As a result, by the time the engineer accumulates enough data to work with, the data may already by obsolete.
It is accordingly an object of this invention to provide a relatively low cost solution to those problems.
It is another object of the invention to provide a timely, powerful, cost effective means of analyzing traffic on the Public Switching Telephone Network (PSTN) to identify unique traffic patterns and the parties involved in such patterns.
It is a further object of the invention to provide a flexible, expedient, accurate, and cost effective method to identify individual destinations (numbers and/or lines) contributing to network blockage. Specifically, it is an object of the invention to provide such a technique to identify numbers or lines associated with Internet Service Providers (ISPs).
It is yet another object of the invention to implement Internet Service Provider (ISP) studies and enable better service to ISP customers while maintaining optimal network utilization.
The invention address the above stated needs by providing effective techniques for tracking traffic through a telecommunication network. The invention encompasses both methods and apparatus for processing records of calls through the network to develop useful data representing patterns of traffic. The invention involves analysis of such data to recognize unique patterns and identify certain types of called parties (e.g. ISPs) from those patterns.
The call records are developed from monitoring or compiling of items of information from certain management data messages used by the network. Management data here refers to information generated by the telecommunication network for its operations purposes, for example, interoffice signaling messages generated to control call set-up and tear-down. Another example of such data would be messages sent from central offices of the network to an accounting office, for record keeping and billing purposes.
In one example of the inventive method, analysis of the call records may identify destinations having a high volume of in-bound traffic. For such destinations, the average hold time or the underlying parameters relating to hold time can be examined.
For ISPs, for example, the average hold time (connect time divided by number of calls) tends to be rather long. If measured using all calls to the numbers (uncompleted as well as completed) the average hold time for ISP calls is greater than eight minutes. If measured using completed calls to the number, the average hold times are even longer. Other types of high traffic destinations exhibit different unique hold time. For example, credit card verification systems typically exhibit a very short average hold time, e.g. less than one minute.
Thus, one aspect of the invention relates to a method involving analysis of data records of calls through a telecommunication network. This analysis identifies destination telephone numbers receiving a high volume of incoming traffic. For the identified destination numbers, data records for calls to those numbers are analyzed to determine the number of calls made to each of the identified numbers and the total amount of connect time for calls to each of the identified numbers. The method collects a subset of the identified numbers. Specifically, the number of calls and the total amount of connect time for calls to numbers in the subset satisfy criteria indicating a target traffic pattern. For example, the connect time and number of calls may indicate a long hold time, e.g. for a target pattern of calls to an ISP.
The present invention identifies destination numbers having an excessive number of incoming calls during some interval, typically an excessive number of calls per day or an excessive number of calls during an hour identified as the peak busy hour for network traffic. In operation, the invention identifies destination addresses or numbers associated with a number of calls during the interval that exceeds a threshold. In one example, the threshold is an arbitrarily selected number representing a high volume of in-bound traffic. An alternative is to select some top number of destinations based on traffic, e.g. the fifteen destination numbers with the highest volumes of in-bound traffic. In this alternative approach, the threshold is essentially the traffic volume of the next lower destination, in the example, the number of calls to the destination number with the sixteenth highest volume of in-bound traffic.
The invention contemplates the possible use of further steps to verify the identified destination as a business of the target type. For example, for ISPs, the analysis would include a further check to confirm that there is no outgoing traffic associated with the number identified as a candidate for that of an ISP. If still further verification is desired, a technician can call the number and detect an answer signal from a modem.
Having identified numbers for particular network users, such as ISP candidate numbers, it is possible to enhance the results of the analysis. Thus, in the preferred embodiments, the inventive analysis may also involve accessing reference data. For example, the list of numbers can be matched against numbers of known ISPs, to reduce the subset to new ISP candidate numbers. Another use of the reference data is to translate an item of information from a data record of a call to one number remaining in the candidate subset into descriptive information. The descriptive information may identify an office of the network assigned to provide switching services relating to the number. As another example, the descriptive information may identify a subscriber that has been assigned the number, e.g. the subscriber acting as the ISP.
Another aspect of the invention relates to a system, for use with a telephone network, for identifying destination telephone numbers as candidate numbers believed to be associated with a particular type of business, e.g. with an ISP. The system includes one or more components associated with the network for compiling detailed records of calls processed through a portion of the telephone network. A server system receives and analyzes the detailed records, to identify each destination telephone number satisfying certain predefined criteria. The criteria for each identified number include the following:
1) calls to the number during a predetermined interval exceed a threshold,
2) calls to the number exhibit an average hold time bearing a predetermined relationship to a threshold duration, and
3) there were substantially no outgoing calls from a station associated with the destination number.
The preferred embodiments of the present invention utilize real time monitors on selected SS7 links to collect interoffice signaling messages. A site processor compiles data from the signaling messages relating to individual calls, to form call detail records (CDRs) for all interoffice call attempts. The site processor uploads the CDRs to a central server. Automatic Message Accounting (AMA) records also are accumulated for at least selected central office switching systems and uploaded to a server. The servers maintain two relational databases, one for the CDRs derived from the signaling data, the other for the AMA based call data sets.
Data from the two relational databases is processed or xe2x80x98preparedxe2x80x99 and uploaded to a multi-dimensional database. The data preparation includes supplementing the records with reference data and where necessary spreading or xe2x80x9cbinningxe2x80x9d usage data to multiple tracking intervals. The multi-dimensional database provides on-line analytical processing tools for enhanced processing of the call data and offers an efficient graphical user interface, preferably a web suite type interface. Applications running in the multi-dimensional database enable analysis and presentation of study results to identify particular traffic patterns and end users. One application, for example, is an ISP finder application.
The preferred embodiment of the on-line analytical processing routine comprises a multi-dimensional database with a presentation layer. The presentation layer may be an independent program or an integral element incorporated in a software package with the multi-dimensional database. The presentation layer provides the user interface, for example in the form of a client-server interface or a web-browser interface. The presentation layer offers the user fast and flexible access to the study data.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.